SOLVED: Error: -69741 while partitioning mac HD

Tried to partition the HD on my new macbook with Diskutil as described here. After decrypting the drive, tried , but was thrown a "Error: -69741: The target disk isn’t eligible for reversion because it wasn’t created by conversion or it is not part of a simple setup of exactly one logical and one physical volume"".

Found the solution at http://apple.stackexchange.com/questions/74803/turn-off-encryption-on-filevault2-second-hdd (boot with command-R > use Diskutil ... created 3 partitions without loosing data).

Image source: osxdaily.com.